Alternative fuel retrofit kit for a combustion engine

Abstract

A retrofit-kit converts an existing internal combustion engine running on gasoline or diesel to run on either the old fuel or an alternative fuel such as compressed natural gas, liquid petroleum, hydrogen, propane, etc. The kit provides a new fuel tank for the alternative fuel, fuel injectors specifically calibrated for the type of alternative fuel used in the kit, as well as gasoline or diesel, and a micro-controller which reads existing engine sensors to allow for fine-tuned injection of the alternative fuel, along with regulation of blow-by gas recycling.

What is claimed is: 
     
         1 . An alternative fuel retrofit kit for an internal combustion engine, comprising:
 a retrofit fuel tank;   a conjunction box fluidly connected to the retrofit fuel tank;   a plurality of fuel injectors fluidly connected to the conjunction box;   a fuel valve in the conjunction box fluidly in-line between the retrofit fuel tank and the plurality of fuel injectors; and   a microcontroller operatively connected to the fuel valve.   
     
     
         2 . The alternative fuel retrofit kit of  claim 1 , further comprising a blow-by gas recirculating system comprising a PCV valve, a vent line fluidly connecting a crankcase of an engine to the PCV valve, and a recirculating line fluidly connecting the PCV valve to the conjunction box. 
     
     
         3 . The alternative fuel retrofit kit of  claim 2 , wherein the microcontroller is operatively connected to the PCV valve and regulates an open/close state of the PCV valve in response to engine sensor signals. 
     
     
         4 . The alternative fuel retrofit kit of  claim 1 , further comprising retrofit fuel injection rails and retrofit fuel injectors. 
     
     
         5 . The alternative fuel retrofit kit of  claim 4 , wherein the retrofit fuel injection rails and retrofit fuel injectors are configured to deliver multiple types of fuel to the engine. 
     
     
         6 . A process for installing a fuel retrofit kit on an internal combustion engine, comprising the steps of:
 installing a retrofit fuel tank in a vehicle containing an engine;   installing a conjunction box in a compartment proximate to the engine;   installing retrofit fuel rails on the engine, wherein the retrofit fuel rails have a plurality of retrofit fuel injectors, each retrofit fuel injector corresponding to one of a plurality of piston cylinders in the engine;   fluidly connecting the retrofit fuel tank to a retrofit inlet on the conjunction box;   fluidly connecting an outlet on the conjunction box to the retrofit fuel rails;   operatively connecting a microcontroller to the conjunction box, wherein the microcontroller regulates a type and amount of fuel passing through the conjunction box.   
     
     
         7 . The process of  claim 6 , wherein the retrofit fuel tank is installed in parallel with an old fuel tank, and further comprising the step of fluidly connecting the old fuel tank to an old fuel inlet on the conjunction box. 
     
     
         8 . The process of  claim 6 , further comprising the steps of removing an old fuel tank from the vehicle, and removing old fuel rails and old fuel injectors from the engine. 
     
     
         9 . The process of  claim 6 , further comprising the steps of installing a PCV valve proximate to the engine, fluidly connecting an inlet on the PCV valve to a crankcase on the engine, and fluidly connecting an outlet on the PCV valve to a blow-by inlet on the conjunction box, wherein the microcontroller blends the blow-by inlet with the fuel inlet. 
     
     
         10 . The process of  claim 6 , wherein the step of fluidly connecting the retrofit fuel tank to a retrofit inlet on the conjunction box further comprises the step of running high pressure tubing and fittings between the fuel tank and the retrofit inlet. 
     
     
         11 . The process of  claim 10 , further comprising the step of clamping the high pressure tubing and fittings to a chassis of the vehicle. 
     
     
         12 . The process of  claim 6 , further comprising the steps of attaching sensor leads from an engine temperature sensor, a PCV valve sensor, a fuel tank sensor, or an exhaust sensor to the microcontroller, and programming the microcontroller with standard values for the engine temperature sensor, the PCV valve sensor, the fuel tank sensor, or the exhaust sensor corresponding to an alternative fuel in the retrofit fuel tank.